EP0283454A1 - Keramisches Schneidwerkzeug, verstärkt mit Whiskern - Google Patents

Keramisches Schneidwerkzeug, verstärkt mit Whiskern Download PDF

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Publication number
EP0283454A1
EP0283454A1 EP88850090A EP88850090A EP0283454A1 EP 0283454 A1 EP0283454 A1 EP 0283454A1 EP 88850090 A EP88850090 A EP 88850090A EP 88850090 A EP88850090 A EP 88850090A EP 0283454 A1 EP0283454 A1 EP 0283454A1
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EP
European Patent Office
Prior art keywords
whiskers
volume
cutting
oxide
whisker
Prior art date
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Granted
Application number
EP88850090A
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English (en)
French (fr)
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EP0283454B1 (de
Inventor
Gunnar Brandt
Zeljka Senesan
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Sandvik AB
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Sandvik AB
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Application filed by Sandvik AB filed Critical Sandvik AB
Priority to AT88850090T priority Critical patent/ATE65773T1/de
Publication of EP0283454A1 publication Critical patent/EP0283454A1/de
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    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/10—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on aluminium oxide
    • C04B35/111—Fine ceramics
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/71—Ceramic products containing macroscopic reinforcing agents
    • C04B35/78—Ceramic products containing macroscopic reinforcing agents containing non-metallic materials
    • C04B35/80—Fibres, filaments, whiskers, platelets, or the like

Definitions

  • the present invention relates to ceramic cutting tool mate­rials and, in particular, to such cutting materials in which monocrystalline whiskers (hair crystals) based upon titanium are homogenously distributed in a ceramic matrix containing aluminium oxide which leads to an improved strength and toughness without having a negative influence on the wear resistance to any appreciable extent.
  • Ceramic cutting tools have now been available for several decades but not until the last ten years they have got a commercial importance for use in chip forming machining. The main reason for the limited increase of ceramic cutting tools has been sudden and unexpected cutting insert fail­ures because of inadequate strength and toughness.
  • Aluminium oxide based cutting tools are very sensitive to thermal cracking as aluminium oxide in itself has a rela­tively low thermal conductivity. This fact leads to a very short life in steel particularly under conditions having short engagement times and varying cutting depths.
  • titanium carbide and/or titanium nitride which improves the thermal conductivity of the composite material.
  • the addition of titanium carbide/nitride also increases the hardness of the materi­al. In comparison with pure aluminium oxide materials an increased life is therefore obtained in cutting of hard workpiece materials and in operations demanding resistance to thermal shocks. This type of material has, however, too poor a toughness behaviour for a general use in cutting of steel.
  • Another, later step of development includes addition of homogenously dispersed fine-grained zirconium oxide parti­cles in a matrix of aluminium oxide.
  • a transformation of the "metastable" zirconium oxide particles at the use increases both strength and toughness and will, thus, lead to a more predictable life.
  • the thermal properties of said kind of material are, howev­er, insignificantly better than those of pure aluminium oxide materials why initiation and growth of thermally induced cracks still are great problems in practical cut­ting operations generating high cutting edge temperatures such as machining of steel.
  • the primary aim of the present invention is to make oxide-­based ceramic cutting materials reinforced by whiskers hav­ing a low solubility in steel resulting in that the cutting material obtains an improved and more predictable tough­ness, strength and thermal shock resistance without appre­ciably deteriorating the wear resistance in cutting of steel, in particular, which has not been possible by earli­er known material compositions.
  • the ceramic cutting material according to the present inven­tion comprises an oxide-based, preferably aluminium oxide-based, matrix with 5-50, preferably 10-40, especially 25-35 % by volume homogeneously dispersed whiskers based upon carbides, nitrides and/or borides of titanium and/or zirconium or in applicable cases solid solutions thereof, preferably titanium nitride.
  • Said whiskers consist of mono­crystals with a diameter of 0.5-10 ⁇ m and a length of 2.5-100 ⁇ m characterised thereof that the length/diameter ratio preferably is 5-10.
  • the grain size of the oxide matrix shall be ⁇ 10 ⁇ m, preferably ⁇ 4 ⁇ m.
  • the oxide matrix shall consist of essentially ceramic oxides or of ceramic oxides mixed with hard carbides and/or nitrides and/or borides and/or binder metal.
  • the ceramic matrix shall contain ⁇ 20 % preferably ⁇ 15 % by weight ZrO2.
  • the above mentioned whiskers may be replaced by silicon carbide whiskers which have a favourable influence on the thermal shock resistance without notably reducing the wear resistance when machining steel under the condition that the total amount of SiC whiskers shall not exceed 15 % by volume.
  • Figs 1 and 2 are SEM photos of the structure of a material according to the invention (Example 1).
  • Fig 1 shows the structure in 300 ⁇ magnification and
  • Fig 2 shows in 3000 ⁇ magnification crack deflection in the structure.
  • the cutting material in question is made by wet milling and mixing of oxide-based powder and monocrystalline whisker crystals. After drying the mixture is pressed to desired geometrical form and sintered without pressure to near theo­retical density. After the sintering the possible remaining so called closed porosity can be removed by a hot isostatic pressing. If it is not possible by sintering to obtain a closed porosity the material can be pressure sintered by a suitable graphite tool or after encapsulating be hot isostatically pressed to desired density. The sintering method is depending upon the whisker material and is chosen so that the cutting material reaches a density which exceeds 99 % of the theoretical density.
  • the whisker material consists of titan­ium nitride and the matrix is aluminium oxide-based, which allows pressureless sintering up to 40 % by volume of whis­kers. Materials containing titanium carbide- or titanium diboride-whiskers cannot be sintered pressurelessly at whis­ker contents above 10 % by volume.
  • whisker reinforcement in the aluminium oxide-based matrix leads to a significant increase of the fracture strength.
  • the mechanisms which cause said increase can be load transfer between whisker and matrix, crack deflection (at arrows in Fig 2) and whisker pull out. These mechanisms utilise and are dependent upon the crack propagation taking place along a sufficiently weak boundary surface between whisker and matrix.
  • the bonding strength between whisker and matrix is therefore an important parameter which can be influenced by coating of the whisker material with thin layers in order to further improve the fracture toughness.
  • whisker-reinforced cutting materials according to the invention.
  • the whisker material being used in the examples has been prepared by CVD-technique but it is obvious to a person skilled in the art that similar results can be obtained by alternative methods of producing the whiskers.
  • Titanium nitride whiskers were made in a CVD-reactor by coating of nickel sponge from a gaseous mixture of TiCl4, N2 and H2 at a temperature of about 1200°C.
  • the whis­ker crystals were removed from the nickel substrate by ultrasonic treatment and mechanical brushing in an acetone bath.
  • the main part of the crystals had a diameter of 0.5-2 ⁇ m and a length of 20-100 ⁇ m.
  • K IC The fracture toughness
  • the fracture toughness is a parameter which shows the ability of a material to resist mechanical stresses without catastrophic failure.
  • chip forming machining it means that higher feeds can be allowed, i.e. the rate of the material removal can be increased for a given cutting speed.
  • Cutting inserts SNGN 120412 were manufactured from 3 powder mixtures according to table 1 and were tested by continuous turning of steel SS 2541.
  • the cutting speed was 450 m/min, the cutting depth 2 mm and the feed 0.36 mm rev ⁇ 1.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Compositions Of Oxide Ceramics (AREA)
  • Cutting Tools, Boring Holders, And Turrets (AREA)
  • Grinding-Machine Dressing And Accessory Apparatuses (AREA)
  • Manufacture Of Alloys Or Alloy Compounds (AREA)
  • Ceramic Products (AREA)
EP88850090A 1987-03-20 1988-03-16 Keramisches Schneidwerkzeug, verstärkt mit Whiskern Expired - Lifetime EP0283454B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT88850090T ATE65773T1 (de) 1987-03-20 1988-03-16 Keramisches schneidwerkzeug, verstaerkt mit whiskern.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE8701172A SE8701172D0 (sv) 1987-03-20 1987-03-20 Whiskerforsterkt keramiskt skerverktyg
SE8701172 1987-03-20

Publications (2)

Publication Number Publication Date
EP0283454A1 true EP0283454A1 (de) 1988-09-21
EP0283454B1 EP0283454B1 (de) 1991-07-31

Family

ID=20367932

Family Applications (1)

Application Number Title Priority Date Filing Date
EP88850090A Expired - Lifetime EP0283454B1 (de) 1987-03-20 1988-03-16 Keramisches Schneidwerkzeug, verstärkt mit Whiskern

Country Status (5)

Country Link
US (2) US4867761A (de)
EP (1) EP0283454B1 (de)
AT (1) ATE65773T1 (de)
DE (1) DE3863946D1 (de)
SE (1) SE8701172D0 (de)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0333776A1 (de) * 1987-05-28 1989-09-27 Kennametal Inc Schneidewerkzeug.
EP0429420A2 (de) * 1989-10-17 1991-05-29 Sandvik Aktiebolag Mit Whiskern verstärktes keramisches Schneidwerkzeugmaterial
EP0441877A1 (de) * 1988-11-03 1991-08-21 Kennametal Inc Keramik-erzeugnisse bestehend aus aluminiumoxyd-zirconiumoxyd-siliziumkarbid-magnesiumoxyd.
EP0468486A1 (de) * 1990-07-25 1992-01-29 Kyocera Corporation Keramischer Werkstoff, verstärkt durch Aluminiumoxid-Fibers und Verfahren zu seiner Herstellung
JPH04503329A (ja) * 1988-11-03 1992-06-18 ケンナメタル インコーポレイテッド アルミナージルコニアーカーバイド　ホイスカーにより強化された切削工具
US5505751A (en) * 1987-05-28 1996-04-09 Kennametal Inc. Cutting tool

Families Citing this family (34)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE8701791D0 (sv) * 1987-04-29 1987-04-29 Sandvik Ab Cemented carbonitride alloy with improved toughness behaviour
DE3812266C1 (de) * 1988-04-13 1989-08-24 Nils Prof. Dr. 2107 Rosengarten De Claussen
US5024976A (en) * 1988-11-03 1991-06-18 Kennametal Inc. Alumina-zirconia-silicon carbide-magnesia ceramic cutting tools
US4959331A (en) * 1988-11-03 1990-09-25 Kennametal Inc. Alumina-zirconia-silicon carbide-magnesia cutting tools
US4960735A (en) * 1988-11-03 1990-10-02 Kennametal Inc. Alumina-zirconia-silicon carbide-magnesia ceramics
US4965231A (en) * 1988-11-03 1990-10-23 Kennametal Inc. Alumina-zirconia-silicon carbide-magnesia compositions and articles made therefrom
WO1990009969A1 (en) * 1989-02-22 1990-09-07 Kabushiki Kaisha Kobe Seiko Sho Alumina ceramic, production thereof, and throwaway tip made therefrom
US5059564A (en) * 1989-06-05 1991-10-22 Kennametal Inc. Alumina-titanium carbide-silicon carbide composition
US5231060A (en) * 1989-10-17 1993-07-27 Sandvik Ab Whisker-reinforced ceramic cutting tool material
AU7169791A (en) * 1989-12-13 1991-07-18 Dow Chemical Company, The Silicon carbide whisker reinforced ceramic composites and method for making the same
JPH04130049A (ja) * 1990-09-18 1992-05-01 Mitsubishi Materials Corp セラミックス複合材料及びその製造方法
US5093975A (en) * 1990-12-04 1992-03-10 The Kinetic Company Method of making new side trimmer and side trimmer blade
SE9100675D0 (sv) * 1991-03-06 1991-03-06 Sandvik Ab Ceramic whisker-reinforced cutting tool with pre-formed chipbreakers for machining
AT394850B (de) * 1991-03-11 1992-06-25 Treibacher Chemische Werke Ag Gesintertes, mikrokristallines keramisches material
US5275984A (en) * 1991-03-13 1994-01-04 Northrop Corporation Fiber coating of unbonded multi-layers for toughening ceramic fiber-matrix composites
SE9100895D0 (sv) * 1991-03-25 1991-03-25 Sandvik Ab Saett att framstaella skaer foeretraedesvis foer skaerande bearbetning av varmhaallfasta material
US5177037A (en) * 1991-05-21 1993-01-05 Industrial Ceramic Technology, Inc. High fracture toughness electro-discharge machineable ceramic whisker reinforced ceramic composites and tooling made therefrom
US5324693A (en) * 1992-10-13 1994-06-28 Mitsubishi Materials Corporation Ceramic composites and process for manufacturing the same
SE502053C2 (sv) * 1993-01-15 1995-07-31 Sandvik Ab Whiskers- och partikel-förstärkt keramiskt skärverktygsmaterial
US5427987A (en) * 1993-05-10 1995-06-27 Kennametal Inc. Group IVB boride based cutting tools for machining group IVB based materials
US5571317A (en) * 1993-07-30 1996-11-05 Western Atlas Inc. Fiber-reinforced magnesium oxychloride bond
US5326731A (en) * 1993-11-18 1994-07-05 Electrofuel Manufacturing Company Ceramic compositions for wear resistant applications
JPH07232959A (ja) * 1993-12-21 1995-09-05 Kobe Steel Ltd アルミナ基セラミックス及びその製造方法
SE508255C2 (sv) * 1994-07-15 1998-09-21 Sandvik Ab Whiskerförstärkt keramiskt material samt metod för dess framställning
US5723213A (en) * 1995-10-18 1998-03-03 Northrop Grumman Corporation Integrated multiple-ceramic-layer fiber interfacial coating
US5665326A (en) * 1995-11-13 1997-09-09 Advanced Refractory Technologies, Inc. Method for synthesizing titanium nitride whiskers
US5932356A (en) * 1996-03-21 1999-08-03 United Technologies Corporation Abrasive/abradable gas path seal system
SE510809C2 (sv) * 1997-07-08 1999-06-28 Sandvik Ab Whiskerförstärkt keramiskt skärverktygsmatierial
SE511312C2 (sv) 1997-12-22 1999-09-06 Sandvik Ab Sätt att tillverka whiskerförstärkt keramik s
US6417126B1 (en) * 2000-02-24 2002-07-09 C-Max Technology, Inc. Ceramics and process for producing
US6905992B2 (en) 2002-07-30 2005-06-14 Kennametal Inc. Ceramic body reinforced with coarse silicon carbide whiskers and method for making the same
CN102503501B (zh) * 2011-11-15 2013-05-15 山东大学 原位生长二硼化锆晶须增韧陶瓷刀具材料及其一体化制备工艺
CN108017392B (zh) * 2017-12-12 2020-08-04 广东工业大学 梯度及非梯度SiCw增韧硼化物基复合陶瓷材料及其制备方法
CN111170755B (zh) * 2019-12-19 2021-11-19 西安交通大学 一种二硼化钛基纳米复合刀具材料及制备方法

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3010545A1 (de) * 1979-03-19 1980-09-25 Ngk Spark Plug Co Gesinterte keramik insbesondere fuer zerspanungswerkzeuge und verfahren zur herstellung derselben
US4366254A (en) * 1980-04-17 1982-12-28 The Valeron Corporation High toughness ceramic cutting tool
EP0133864A1 (de) * 1983-06-30 1985-03-13 Hitachi Metals, Ltd. Keramik für Schneidwerkzeuge
GB2157282A (en) * 1984-04-06 1985-10-23 Santrade Ltd Nitride-based ceramic material
EP0194811A2 (de) * 1985-03-14 1986-09-17 Advanced Composite Materials Corporation Verstärkte keramische Schneidwerkzeuge
EP0252046A2 (de) * 1986-06-19 1988-01-07 Sandvik Aktiebolag Beschichteter, gesinterter, mit Whiskern verstärkter Keramikkörper
EP0208910B1 (de) * 1985-06-10 1989-04-12 NGK Spark Plug Co. Ltd. Faserverstärkter Verbundwerkstoff für Werkzeuge

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4343909A (en) * 1980-04-17 1982-08-10 The Valeron Corporation High toughness ceramic cutting tool
DE3518844A1 (de) * 1985-05-24 1986-11-27 Max-Planck-Gesellschaft zur Förderung der Wissenschaften e.V., 3400 Göttingen Keramischer verbundwerkstoff
US4789277A (en) * 1986-02-18 1988-12-06 Advanced Composite Materials Corporation Method of cutting using silicon carbide whisker reinforced ceramic cutting tools
US4852999A (en) * 1987-05-28 1989-08-01 Kennametal Inc. Cutting tool
US4925458A (en) * 1987-05-28 1990-05-15 Kennametal Inc. Cutting tool

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3010545A1 (de) * 1979-03-19 1980-09-25 Ngk Spark Plug Co Gesinterte keramik insbesondere fuer zerspanungswerkzeuge und verfahren zur herstellung derselben
US4366254A (en) * 1980-04-17 1982-12-28 The Valeron Corporation High toughness ceramic cutting tool
EP0133864A1 (de) * 1983-06-30 1985-03-13 Hitachi Metals, Ltd. Keramik für Schneidwerkzeuge
GB2157282A (en) * 1984-04-06 1985-10-23 Santrade Ltd Nitride-based ceramic material
EP0194811A2 (de) * 1985-03-14 1986-09-17 Advanced Composite Materials Corporation Verstärkte keramische Schneidwerkzeuge
EP0208910B1 (de) * 1985-06-10 1989-04-12 NGK Spark Plug Co. Ltd. Faserverstärkter Verbundwerkstoff für Werkzeuge
EP0252046A2 (de) * 1986-06-19 1988-01-07 Sandvik Aktiebolag Beschichteter, gesinterter, mit Whiskern verstärkter Keramikkörper

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0333776A1 (de) * 1987-05-28 1989-09-27 Kennametal Inc Schneidewerkzeug.
EP0333776A4 (de) * 1987-05-28 1989-10-24 Kennametal Inc Schneidewerkzeug.
US5505751A (en) * 1987-05-28 1996-04-09 Kennametal Inc. Cutting tool
EP0441877A1 (de) * 1988-11-03 1991-08-21 Kennametal Inc Keramik-erzeugnisse bestehend aus aluminiumoxyd-zirconiumoxyd-siliziumkarbid-magnesiumoxyd.
EP0441877A4 (en) * 1988-11-03 1992-02-26 Kennametal Inc. Alumina-zirconia-silicon carbide-magnesia ceramic articles
JPH04503329A (ja) * 1988-11-03 1992-06-18 ケンナメタル インコーポレイテッド アルミナージルコニアーカーバイド　ホイスカーにより強化された切削工具
EP0429420A2 (de) * 1989-10-17 1991-05-29 Sandvik Aktiebolag Mit Whiskern verstärktes keramisches Schneidwerkzeugmaterial
EP0429420A3 (en) * 1989-10-17 1992-10-28 Sandvik Aktiebolag Whisker-reinforced ceramic cutting tool material
EP0468486A1 (de) * 1990-07-25 1992-01-29 Kyocera Corporation Keramischer Werkstoff, verstärkt durch Aluminiumoxid-Fibers und Verfahren zu seiner Herstellung
US5360772A (en) * 1990-07-25 1994-11-01 Kyocera Corporation Ceramic material reinforced by the incorporation of TiC, TiCN and TiN whiskers and processes for production thereof

Also Published As

Publication number Publication date
JPS643065A (en) 1989-01-06
DE3863946D1 (de) 1991-09-05
EP0283454B1 (de) 1991-07-31
ATE65773T1 (de) 1991-08-15
USRE35090E (en) 1995-11-21
US4867761A (en) 1989-09-19
SE8701172D0 (sv) 1987-03-20

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